I wouldn't say that the PlayStation Move isn't referencial of the Wii Remote, but the fact of the matter is that the technology that is used in the device has been in development since before the Wii Remote was ever shown. Furthermore, the technology is fundementally different in the way it works with the PlayStation Eye from the Wii Remote and Sensor Bar.
So Sony didn't copy the idea. They didn't copy the technology. What did the copy? The appearance? The "Sub-Controller"?
Well the appearance is really not so similar to the Wii Remote that it can be called a copy. I certainly don't see a big glowing ball at the end of a Wiimote and even the form factor (a cylinder rather than a box) is completely different. Then there's theres the button schemes that have even less in common than a DualShock and a Classic Controller.
So in the end the only thing about the PlayStation Move that can reasonably be called a "clone" of Nintendo would be the idea of a sub-controller. However that has been something that the fans have been demanding that Sony create ever since they first unveiled the Motion Controller prototype at E3 last year, so you really can't blame Sony for giving everybody what they wanted. Well, I'm sure the most rabid of the Nintendo fanboys can find a way.